Docking & translation - explain in small words please

[Clear Air Turbulence]

Apologies for asking such a simple question. I have looked around on forum but can't seem to find an answer.

When I am (trying to) dock and I am very close to other craft... And I am in RCS mode... and I am using the translation keys (HNIKJL) to move up and down, forward and backward....

How do I figure out what's up and down?

I just can't seem to figure it out. is it in relation to the navball? It does not seem to be...

Is it in relation to the target?

Some part of the ship?

It is doing my head in.

I have looked at any number of docking tutorials, read the wiki, and checked out any number of forum threads, and everyone mentions this in passing as if it is the most obvious thing in the world. But there is clearly something I am just not getting...

I'd be grateful for any small hints. Short sentences, and baby words please.

Edited October 6, 2015 by Clear Air Turbulence

[BenG]

Hit the V key until the camera mode is "locked". Now the movement of fhe ship will be in the direction you expect whilst looking at it from directly behind.

Also, get the docking port alignment indicator mod. It makes docking so easy.

[pandaman]

Hi. hope this helps...

Translation means moving left, right, up or down (and I think the term also includes moving forward and back) or any combination of these without turning or rotating the ship.

Using a spaceplane as an example, forward and back are along the length of the ship (that is nose to tail).

Translating up is like grabbing it in the SPH and moving the whole ship directly up towards the ceiling, translating down is towards the floor. Left and right are the same but to the sides.

A rocket works exactly the same, forward and back are still nose to tail along the length, but in the VAB this is vertical (capsule to engines). Up, down, left and right are relative to this with UP being to your right as you look directly out through the VAB doors. As the ship sits on the pad when you go to launch the UP is towards you (the same directions as the WASD keys)

It can be difficult to know which way to your ship is rotated as most rockets are circular and symmetrical which makes it hard to determine UP for translation. I suspect that is your problem, try adding a light or small solar panel on the UP side of your ship to serve as a visual reference.

Cheers

[Delta-Cheese]

I am pretty sure forward and backwards are always correct (H & N), but at least two directions (up or down, I & K, or left and right ,J & L) will be inverted, but I may be wrong.

[Red Iron Crown]

I just can't seem to figure it out. is it in relation to the navball? It does not seem to be...

It is, or more precisely, the navball forward direction is set the same way as the HNIJKL orientations.

Is it in relation to the target?

No.

Some part of the ship?

Yes. The part from which the vessel is being controlled (i.e. Control From Here has been selected in the right click menu) determines orientation. Usually this is a docking port during docking (most tutorials will tell you to control from the port as one of the first steps).

BenG's advice to use "Locked" camera mode is good, that way the orientation doesn't change relative to the camera. I also find it useful to have the up side of the vessel marked visually, either by using asymmetric parts like the inline Mk1 cockpit or by placing a small part of the "top" side of the vessel. Example pic, the single light on this tug serves both as an aid in dark docking and an easy reference for which side is "up".

[Tank Buddy]

I have a few suggestions:

• Change your translation controls to the arrow keys and RShift and RCtrl. This way you actually know what key does what. (Whether you assign 'up' or 'forward' to RShift or the up arrow is up to you, I have up arrow as forwards, so translation relative to the camera on xz is through the arrow keys)
  
• Press V and change your view to "locked"; This locks the camera to the orientation of the craft so up/down, left/right, and forward/back are always the same relative to the camera.
  
• Set the docking port you want to dock to as a target, and use the navball in target mode to navigate. Line up prograde with the target indicator, and you will be on your way. Practice makes perfect. There are a lot of specifics, like facing the docking port and not flying into your target that you will have to nail down by experience.
  

[BenG]

Sorry, my first reply was brief due to being on my mobile, not in front of my PC, but it seems Red Iron Crown has you covered.

One big thing to be aware of is that the controls are relative to the part which the vessel is currently being controlled from. If this is at the nose of the vessel and oriented in the same way as the command module, then pandaman's advice is absolutely correct. If you are attempting to use a radial docking port or otherwise unusual location, then it may not be so simple.

I personally like using locked camera mode as I can then watch the vessel as I am docking rather than the nav ball (which I personally find not to be the greatest tool when trying to dock), and it behaves exactly as expected, although visual cues on the vessel itself are a great idea which I must admit I never thought of myself.

However, I would again suggest checking out the docking port alignment indicator mod. It really does make docking so much easier than using just the nav ball.

[Clipperride]

As others have said switching to the locked view will show you which side is which. Once you know that, you can swap back to whichever view is easiest.

Other things that make docking easier are:

Carefully place your RCS thrusters. You don't want to induce any roll, pitch or yaw when you just want to translate. Placing thrusters an even distance either side of the stages CoM really helps. Also, place them 90° apart so they don't "fight" each other. In flight, when looking at your ship from one end, the pattern made by the exhaust from the thrusters should make a square/diamond pattern.

Keep your speed down. It's better to move in at a low speed and use the time warp to speed things up. The each time you translate in one direction, you spend an equal amount of fuel stopping again.

Whilst getting the hang of docking, move one plane at a time. It's much easier to keep track of movement relative to your target when you keep things simple.

Learn to use the NAV ball. The prograde marker can really help show if you are just moving towards or away from your target, or if you have movement in any other plane messing things up. Moving a couple of m/s towards or away from your target should place the prograde/retrograde marker in the middle of the NAV ball. If its a little off, you can use the RCS thrusters keys to centre it and stop any unwanted movement.

[Clear Air Turbulence]

I did it. :cool::cool:

don't ask me how

Somehow I got both ships' noses to touch - not at all aligned & then we sort of nuzzled like drunken whales until the magnetism of the docking port finally took over

Without the docking port alignment indicator, which somehow does not want to work on my system. Without navball. Just sort of eyeballing the orientation of the two craft in relation to each other.

Locked view definitely helped a lot, thanks for that tip!

Anyway, thanks for the help.

Now I just have to figure out how to do it again:)

Edited October 4, 2015 by Red Iron Crown

[Clipperride]

Well done! Honestly, it does get easier with practice! As you've seen, once gentle contact is made, the magnets usually do the rest. Turning off SAS can often help the magnets do their job to. One more thing that can help; if your target docking port is the far side from you, swap to the target ship and change its attitude to match the docking ships.

Here's a link to using the NAV ball to help close those final few metres

[pandaman]

@Clear Air Turbulence. ..

Nice one. Pleased to hear you made it. Congratulations. The cosmos is now yours for the taking.